Metal casting apparatus

ABSTRACT

A low-pressure metal die casting furnace including a top diesupporting structure mounted on a cantilevered support capable of pivotal movement about a vertical column at one side of the furnace, and also capable of vertical movement under control of a ram to give access to the furnace top. The ram controlling the top die structure can also be coupled to a lower die-supporting plate, to raise the plate. A single mechanism can serve two adjacent furnaces.

United States Paten Carlsen Feb.22, 1972 [54] METAL CASTING APPARATUS [72] lnventor: Jon E. M. Carlsen, 2 Western Ave., Newport, Monmouthshire, England [22] Filed: Dec. 16, 1969 [21] Appl. No.: 885,544

[30] Foreign Application Priority Data Dec. 21, 1968 Great Britain ..60,901/68 [52] US. Cl ..l64/309, 164/119, 164/137, 164/341, 164/343 [51] Int. Cl. ..B22d 17/06, B22d 33/04 [58] FieldoISeareh ..l64/l13, 119,131,137, 303, 164/306, 309, 312, 316, 317, 318,335,136, 339,

[56] References Cited UNITED STATES PATENTS 1,944,199 l/l934 Tischler ..l64/3l7 2,105,586 l/l938 Daesen et a1. ..l64/1l3 FOREIGN PATENTS OR APPLICATIONS 81,646 7/1919 Switzerland ..l64/l 19 Primary Examiner-J. Spencer Overholser Assistant Examiner-John E. Roethel Attorney-Hall, Pollock & Vande Sande [57] ABSTRACT A low-pressure metal die casting furnace including a top diesupporting structure mounted on a cantilevered support capable of pivotal movement about a vertical column at one side of the furnace, and also capable of vertical movement under control of a ram to give access to the furnace top. The ram controlling the top die structure can also be coupled to a lower die-supporting plate, to raise the plate. A single mechanism can serve two adjacent furnaces.

5 Claims, 3 Drawing Figures PATENTEDFEB22 m2 SHEET 2 BF 2 I I l l I 1 I ATTORNEY METAL CASTING APPARATUS This invention relates to metal casting apparatus and in particular to apparatus for mounting a die or die assembly on a furnace of a low-pressure die casting apparatus.

According to one aspect of the invention apparatus for mounting a die or die assembly on a furnace comprises means for supporting a die or die assembly, means for vertically elevating the die or die assembly supporting means, and means for horizontally swinging the die or die assembly supporting means when elevated.

Preferably the vertically elevating means is mounted on the horizontally swinging means.

The horizontally swinging means may include a cantilever arm.

In the case in which the vertically elevating means is mounted on the horizontally swinging means it may be mounted on a further cantilever arm which is arranged to swing with the first-mentioned cantilever arm.

The vertically elevating means may comprise a double-acting hydraulic ram. 7

The invention also includes a die casting apparatus including a die mounting apparatus as mentioned above.

From another aspect of the invention a die mounting structure for a low-pressure die casting apparatus comprises a frame for mounting on a furnace, the frame including a member for supporting a die, means movable towards and away from the frame member and having means for attachment to the member to raise and lower the member, and means mounting the die moving means for pivotal movement about a vertical axis from a first position above the die supporting member to a second position clear of the first.

The frame may comprise a lower plate for supporting a die and an upper plate carrying the die moving means, the plates being pivotable together about the vertical axis.

The lower plate may comprise upper and lower parts releasably secured together, the upper part being arranged to support a die and to carry a feed nozzle, the lower part being ivoted on the vertical axis.

The upper and lower plates may each have a curved slot spaced from the vertical axis arranged in the first position to embrace a vertical rod, and releasable clamping means may be provided for clamping the plates and rod together in the first position.

The invention also includes a die casting apparatus including a die mounting structure as mentioned above.

The invention can be performed in several ways and one example of a die mounting structure and die casting apparatus according to the invention will now be described by way of example, reference being made to the accompanying diagrammatic drawings in which:

FIG. 1 is an elevation ofa die mounting structure;

FIG. 2 is a plan view, on a reduced scale, in the direction of the arrow A in FIG. 1, and

FIG. 3 is a diagrammatic illustration of a twin furnace assembly.

A die mounting structure is indicated generally at and comprises a frame 11. The frame 11 includes two support structures l2, 13 which in use are fixed, for example by integral threaded studs 14, in the top plate 15 ofa melting furnace of a low-pressure die casting apparatus.

As is known, the melting furnace is provided with means for introducing gas under pressure into a melting pot in the furnace. A feed duct shown dotted at 16 extends through an opening in the top plate 15 and in use carries molten metal moved by the gas from the melting pot to a die supported in the die mounting structure 10.

The devices for supplying gas under pressure to the furnace, and the melting pot, and the furnace, may be conventionally arranged and are not shown.

The frame 11 includes two vertical metal columns l7, 18 fixed respectively to the structures 12, 13. At their upper ends the columns 17, 18 are tied together by a metal bar 19 which has apertures which received portions 20, 21 of the columns of reduced cross section and which is held in place by nuts 22, 23.

A sleeve 24 surrounds part of column 17 and is rotatable on the column on vertically spaced bearings 25, 26 and a thrust bearing 27. The lower end of the sleeve is of reduced cross section and extends through an aperture adjacent one end ofa lower horizontal elongated steel plate 28. Upward movement of plate 28 is prevented by a shoulder on the sleeve and downward movement prevented by the bearing 27.

The upper end of the sleeve is of reduced cross section and extends through an aperture in an upper horizontal steel plate 29. Downward movement of plate 29 is prevented by a shoulder on the sleeve and upward movement prevented by a clamp 30. The plates 28, 29 act as cantilever arms. and rotate with the sleeve 24. The opposite ends of the plates are held apart by a vertical plain steel rod 31 fixed at its ends to the plates, curved slots 32, 33 being respectively formed in the plates adjacent the rod 31. In the position shown, the column 18 is received in the bases of the slots 32, 33 and the plates are firmly held in position by clamps 34 (only the upper one being shown) similar to the clamp 30. The upper clamp 34 comprises two nuts on a threaded portion of the column 18 of reduced cross section.

The feed duct 16 which dips into the melting pot of the furnace and presents a free open mouth to the metal in the pot is supported in a collar shown dotted at 50 which rests in a recess in the furnace top plate 15. A feed nozzle 51 is separable from the duct 16 and in the position shown forms a continuation of the duct 16. A seating surface on the lower end of the injection nozzle 51 is adapted to engage a seating surface on the collar 50, the nozzle being formed with a bore through which molten metal may pass through the duct 16 and the collar 50 to a casting cavity. The nozzle 51 has a flange 66 adjacent its upper end and is fixed by bolts 65 to and depends from a fixed half-die 35 which in turn is fixed to a lower fixed platen 52 in the form of aplate which is releasably secured to the upper surface of the plate 28, the plate 52 being received by threaded studs fixed to the plate 28, and held in position by nuts 36 with interposed washers 39.

Support rods 42 are fixed at their lower ends to the plate 28 and have threaded upper ends 43 held in the upper plate 29 by nuts 44.

A steel plate or platen 45 shown in full lines in its most upward position is guided for upward and downward movement by vertical rods 46 extending through corresponding apertures in the upper plate 29 and is secured to the piston 47 of a hydraulic ram 48 carried by the plate 29. Conventional means not shown are provided for operating the hydraulic ram. A movable half-die 63 only shown dotted in a lowered position is firmly but releasably secured to the undersurface of the plate 45. The die 63 in a fully lowered or casting position engages the fixed die 35 to define a casting cavity 60.

The plate 45 carries hooklike straps 49, which may be held by means not shown in a horizontal position, and which can respectively pivot about horizontal axes 64, 61. The plate 52 carries studs 62 or the like which can be engaged by hooklike ends of the straps 49 when these are released from their horizontal position.

On operation of the ram 48, the die 63 is repeatedly moved into and out of the casting position in which it is closed on the die 35 to form a succession of similar cast articles. When die 63 is raised it is arranged to carry with it a cast article and conventional means not shown are provided for removing a cast article from die 63 as the die 63 is raised. Alternatively, a cast article could be removed by hand.

If it is desired to replace a die 63 and 35 or to gain access to the feed duct 16 or to the interior of the furnace, for example for refilling or relining the furnace, the ram 48 is operated to lower the die 63 and the plate 45 until the straps 49 when released can be brought to engage the studs 62. After releasing nuts 36, the ram 48 is again operated to raise plate 52, and with it the die parts 35 and 63, through straps 49, the plate being guided by the rods 42. During this upward movement,

the connection between the nozzle 51 and the feed duct 16 is broken by about one-half inch to 1 inch. The clamps 34 are then released, so that the mounting assembly can pivot with a horizontal swinging movement about column 17 to move plates 28, 29 and the whole die assembly and nozzle 51 away from the furnace to provide free access to the furnace.

After pivoting, which is easily effected, the die 63, 35 may be removed and replaced by another die, whereafter the assembly may be returned to its original position over the duct 16, the clamps 34 secured and the ram operated to lower the die 63 to the operative position.

The assembly can pivot about the vertical axis through 180 and if desired can be used to move a whole die and the feed nozzle from one furnace to another furnace mounted adjacent to the first furnace, as illustrated in FIG. 3, where the two furnaces 70, 71 are mounted side-by-side, with a common central supporting column 17, and one-pivoted die-supporting structure 24, 28, 29, 48, etc., can swing from one furnace across to the other, leaving one furnace completely clear for maintenance while the other is in use.

What I claim is:

l. A die mounting structure for a low-pressure die casting apparatus, comprising a frame adapted to be mounted on a furnace, said frame including a lower, substantially horizontal, die-supporting plate member, an upper, substantially horizontal, plate member, and powered means arranged to move said upper plate member vertically towards and away from the lower plate member, in which there are provided attachment means capable of connecting the upper and lower plate members for simultaneous vertical movement and means mounting the upper plate member for pivotal movement about a vertical axis, whereby the lower plate member can'be attached to the upper plate member, raised by the powered means and swung laterally away from the furnace about the vertical axis.

2. A structure as claimed in claim 1, in which the lower plate member is pivotally mounted on the said vertical axis.

3. A structure as claimed in claim 2, in which the lower plate member comprises an upper part releasably secured to a lower part, the upper part being arranged to support the die and to carry a feed nozzle, the lower part being pivoted on the said vertical axis.

4. A structure as claimed in claim 2, in which each plate member has a curved slot spaced from the vertical axis, which slots receive a vertical rod when the plate members are in position for casting, and releasable clamping means are provided for clamping the plate members and rod together in that position.

5. A structure as claimed in claim 1 in which the powered means is a hydraulic ram having a vertically movable piston connected to the upper plate member.

lOl024 0354 

1. A die mounting structure for a low-pressure die casting apparatus, comprising a frame adapted to be mounted on a furnace, said frame including a lower, substantially horizontal, diesupporting plate member, an upper, substantially horizontal, plate member, and powered means arranged to move said upper plate member vertically towards and away from the lower plate member, in which there are provided attachment means capable of connecting the upper and lower plate members for simultaneous vertical movement and means mounting the upper plate member for pivotal movement about a vertical axis, whereby the lower plate member can be attached to the upper plate member, raised by the powered means and swung laterally away from the furnace about the vertical axis.
 2. A structure as claimed in claim 1, in which the lower plate member is pivotally mounted on the said vertical axis.
 3. A structure as claimed in claim 2, in which the lower plate member comprises an upper part releasably secured to a lower part, the upper part being arranged to support the die and to carry a feed nozzle, the lower part being pivoted on the said vertical axis.
 4. A structure as claimed in claim 2, in which each plate member has a curved slot spaced from the vertical axis, which slots receive a vertical rod when the plate members are in position for casting, and releasable clamping means are provided for clamping the plate members and rod together in that position.
 5. A structure as claimed in claim 1 in which the powered means is a hydraulic ram having a vertically movable piston connected to the upper plate member. 